University College London and Imperial College say they are considering a merger - which could take place as early as next year.

The two prestigious central London institutions say that joining together could help them become a "global player" in the increasingly international higher education market.

"This would allow us to stand alongside major institutions around the world," said Dr Alisdaire Lockhart, spokesperson for University College London (UCL).

Sir Alexander Fleming was one of Imperial College's Nobel laureates

The two colleges are among the most academically successful in the United Kingdom.

In last year's research league tables, only Oxford and Cambridge had more top-graded departments than UCL.

And Imperial College, which has a worldwide reputation for science and technology, can claim 14 Nobel laureates, including Sir Alexander Fleming, for the discovery of penicillin.

'Critical mass'

Combining resources and departments would help a merged university to develop the "critical mass" necessary for world-class research, said Dr Lockhart.

But he promised that this merger was being driven by academic and not economic need - and said that he did not anticipate any academic staff cuts.

The combined universities would have 3,000 academic staff, 3,000 research staff and 4,000 research students.

The merger would need an Act of Parliament to be formalised, but Dr Lockhart indicated that in "operational" terms, the two universities could be under a single leadership by autumn 2003.

'Super-university'

It is anticipated that a merged "super-university" would still occupy a number of different campuses in London - but that departments in the two institutions would be integrated.

No name has so far been chosen for the merged colleges.

At present, the two colleges are members of the over-arching University of London, which also includes colleges such as the London School of Economics, King's College, Goldsmiths and Queen Mary.

But it is expected that a combined UCL and Imperial would abandon the federal structure - which was first established in 1836 and is claimed as the biggest university in Britain.

Universities in the United Kingdom have been facing increased pressures on funding - and the likelihood of mergers has been predicted.

But this would be by far the most significant merger - bringing together two of the country's most presitigious academic institutions.

'Globalisation'

Imperial College, founded in 1907, has an international reputation for excellence in science, technology and medicine.

In last year's research assessment, more than half its departments scored the highest 5* grade, one of the best research records in the UK.

After Oxford and Cambridge, UCL describes itself as the next oldest university in England, founded in 1826.

UCL was the first to admit women on equal terms with men - and the first to admit students of all races and religions.

A statement from the universities said: "The two colleges have now decided, in response to opportunities in the globalisation of education and research, and to their interpretation of current government policy in these areas, to embark on a collaborative process that could lead to the decision to merge these two Institutions into a new University."